Data is recorded on materials such as magnetic tapes and optical discs, which are contained in cartridges for both protection and ease of handling. Many of such cartridges may be stored in what is known as data storage libraries for potential later use.
Typically, the media is initially introduced into the library through a so-called mail slot or simply by hand placement. The media is then stored in one of many storage slot locations throughout the library. When there is a desire to use the media, the media is transferred from a storage slot via a transport assembly or robot to a drive for the operations of either writing data onto or reading data from the media. Upon completion of that operation, the media is returned via the robot to the same or a different storage slot for possible future use.
Each robot has a sophisticated picker assembly designed to grasp media from a storage slot, retain the media during transport within the library, insert and deposit the media into the drive, grasp and retrieve the media from the drive, retain the media during transport back to a storage slot, and insert and deposit the media into the storage slot. The picker assembly is designed and configured to accommodate the structure and other characteristics of the particular media employed in the data storage library.
Each picker assembly usually includes a carriage provided with clamps or jaws designed to grasp the media at opposing surfaces and includes software and other mechanisms designed to selectively grasp, move, and release the media.
Most carriages are electromechanically controlled and operated via motors or solenoids that are selectively activated to perform the grasping, moving, and releasing functions of the carriage. The present invention relates to a so-called “passive” carriage in which the grasping, moving, and releasing functions are accomplished without conventional electromechanical actuation. Accordingly, the present invention achieves savings by tending to lower the cost of construction, operation, and repair of, and by improving the reliability of operation of, picker assemblies employed in data storage libraries.